TSI Instruments HM685, Owner'S Manual

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8-2 Hydronic Manometer Model HM685
4. Turn the valve handle on the manometer to the MEASURE position.
5. Hold the manometer with the pressure ports directed downward to
allow liquid to drain from the unit.
Note: The HM685 Hydronic Manometer should be stored with the valve
handle in the MEASURE position.
In-Line Flow Restrictor
The blue and red hose assemblies include flow restrictors. The flow
restrictors must be used to prevent damage to the pressure sensors from
unexpected water hammering or pressure spikes and also acts as a filter.
Do
not use the HM685 Hydronic Manometer without the flow restrictors
installed in the hose assemblies or sensor damage or clogging will occur.
Flow Restrictor
Shut-Off Valve
Short Hose Section
Cleaning the In-line Flow Restrictors
These flow restrictors should be flushed periodically with clean water to
minimize potential clogging.
1. Disconnect the hose from the manometer.
2. Turn the shut-off ball valve on the hose to the closed position.
3. Connect the straight female flare fitting (farthest from the hose shut-off
valve) on the hose to a suitable water source.
4. Place the open end of the hose in a suitable receptacle or near a drain.
5. Turn the shut-off ball valve on the hose to the open position and allow
water to flush through for several minutes.
6. Using a suitable high pressure air source, blow the entrained water
from the hose.
7. Repeat with the second hose.
Note: If necessary, remove the flow restrictor for further cleaning or
flushing. Reattach to hose assembly when complete.
Cleaning the Instrument Housing
The HM685 Hydronic Manometer may be cleaned using a soft, damp,
clean cloth.
Note: Solvents or abrasive cleaners should never be used to clean the
instrument housing, keypad, or display.